$5+7=125+7=12$

$\circ \circ \circ \circ \circ +\circ \circ \circ \circ \circ \circ \circ \backslash circ\backslash circ\backslash circ\backslash circ\backslash circ\; +\backslash circ\backslash circ\backslash circ\backslash circ\backslash circ\backslash circ\backslash circ$ $=\circ \circ \circ \circ \circ \circ \circ \circ \circ \circ \circ \circ =\backslash circ\backslash circ\backslash circ\backslash circ\backslash circ\backslash circ\backslash circ\backslash circ\backslash circ\backslash circ\backslash circ\backslash ;\backslash circ$